Ionospheric effects of geomagnetic storms at mid latitudes.

Previously, we studied the ionospheric effects of the sequence of geomagnetic storms on September 9-14, 2005 using a global self-consistent model 'Thermosphere-Ionosphere-Protonosphere' (GSM TIP). Differences between the predicted and observed effects of the ionospheric storms may be due to the use of the three-hour K index of geomagnetic activity in modeling the time dependence of model input parameters, use of the dipole approximation of the geomagnetic field, and disregard in simulations for solar flares that occurred during this period. We tried to eliminate two of these three reasons. First, we used the A index of geomagnetic activity with minute resolution in modeling the time dependence of the model input parameters. Second, we took into account the effects of solar flares. In addition, GSM TIP model was supplemented by an empirical model describing the precipitation of high-energy electrons. The results of the simulation of the behavior of various ionospheric parameters over the Yakutsk, Irkutsk, Millstone Hill, and Arecibo stations on September 9 and 10, 2005 in the new formulation of the problem, presented in the current work, are in better agreement with the available experimental data than the results of previous calculations. [ABSTRACT FROM AUTHOR]